Hitachi TRK 902 Service Manual

Page 1

@ HITACHI
SERVICE MANUAL

@ (2/ (24 \@2\®

KEY TO ILLUSTRATIONS

CONTROLS
CD HEADPHONES SOCKET
2) FM STEREO INDICATOR
I3> VOLUME CONTROL
3) SPEAKER/INNER MIC. SELECTOR
5) DIAL POINTER
@ FM MODE/RIF SELECTOR
(,7) FUNCTION SELECTOR
AM BAND SELECTOR
TUNING CONTROL
INNER MICROPHONE (MONAU RALI
GRAPHIC EOUALIZER CONTROLS
PAUSE BUTTON
I STOP/EJECT BUTTON

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TY No. 540E

TRK-902

5,5(35),w

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CONTENTS
KEY TO ILLUSTRATIONS ........... 1
SPECIFICATIONS .................. 2
DISASSEMBLY .................... 3
TUNING DIAL POINTER

ADJUSTMENT .................. 4
ADJUSTMENT ................ 5,6, 7
INSPECTION OF MECHANISM ....... 8
LUBRIFICATION .................. 8
PRINTED WIRING BOARD .......... 9
CIRCUIT DIAGRAM ............... 1O
BLOCK DIAGRAM ................ 13
EXPLODED VIEW .............. 14,15
REPLACEMENT PARTS LIST ..... 16-18

FAST FORWARD BUTTON
REWIND BUTTON
PLAYBACK BUTTON
RECORD BUTTON
CASSETTE HOLDER
CD/LINE IN SOCKET
SPEAKER TERMINALS
TELESCOPIC ANTENNA (AERIAL)
AC/BATT. SELECTOR

DCQV SOCKET (for W)
VOLTAGE SELECTOR (for W)

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CORD CLAMP

SPEAKER ASSEMB LY/REMOVAL TABS

SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT.

minim/1m nAnIo CASSETTE TAPE RECORDER

January 1987

TOYOKAWA WORKS

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HITACHI TRK-902

SAFETY PRECAUTION

The following precautions should be observed when servicing. . . .
1. Since many parts in the unit have special safety related characteristics, always use genurne Hitachi's rev

placement parts.

Especially critical parts in the power circuit block should not be replaced with other makers. Critical
parts are marked with A in the circuit diagram and printed wiring board.

2. Before returning a repaired unit to the customer, the service technician must thoroughly test the unit to
ascertain that it is completely safe to operate without danger of electrical shock.

SPECIFICATIONS

General Section

Semiconductors

Power supply

Power Consumption
Power Output
Speakers

Dimensions Weight

Radio Section
Circuit System

Tuning Range

Intermediate
Frequency

ICs: 5
Transistors: 6 (For W, E (38)]

7 [For E]
Diodes: 6
LEDs: 1
AC: 220V, 50Hz [For E]
AC: 240V, 50Hz {For E (B8)]
AC: 110-127V/200~22OV
230v250V, 50/60H2 [For W]
DC: 9V (D" CELL or IEC R20

x 6 or equivalent)

Car: Use car battery adaptor (9V)
16W
1.8W/CH (T.H.D. 10% DC)
10cm, 4 ohms x 2
2cm, 300 ohms x 2
540 (W) x 205 (H) x 167 (D) mm
4.5kg (with batteries)

FM/SW/MW/LW 4-band
[For E, E (38)]
FM/SWZ/SWl/MW 4-band
(For W]
Super heterodyne
FM: 87.5 to

108 MHz
SW: 6.0 to

18.0 MHZ
MW: 530 to

1,605 kHz
LW: 150 to

285 kHz
FM: 88 to

108 MHz
SW2: 7.0 to
22.0 MHz
2.3 to
7.0 MHz
MW: 530 to

1,605 kHz
FM: 10.7 MHz
AM: 465 kHz [For E. E (88)]
AM: 455 kHz [For W]

For E, E (BS)

SW1: [For W}

Sensitivity FM: 14 dB( pra.)
8dB( max.)
SW: 30 dB (pra ),)
20 dB max
MW: 50 dB (pra) [For E'HBS
40 dB (max.)
LW: 55 dB (pra)
46 dB( max.)
FM: 14 dB( pra. ),
6 dB (max. )
SW2: 30 dB (pra)
24 dB( max. )
: 46 dB (pra. ).
38 dB (max )
MW: 50 dB (pra)
40 dB (max. )
FM/SW: Rod antenna
MW/LW: Built- -in ferrite core }
antenna
FM/SW2: Rod antenna
SWI/MW: Built-' in ferrite core }
antenna

SW1 [For W]

Antennas
(Aerials)

[For E, E (83)]
[ForW]

Tape Recorder Section

Tape

Track System

Tape Speed
Recording System
Erasing System
Frequency Response
Signal to Noise Ratio
Wow and Flutter
Cross Talk

Distortion

Erasing Ratio

Motor

Heads

input Sensitivity and
Impedance
Headphones output
Impedance

Speaker Output
Impedance

Cassette tape (C-30, 60, 90)
4 track 2 channel stereo
4.75 cm/sec.

AC bias. 58 kHz

Magnet

Normal: 60 to 10000 Hz
40 dB

0.25% (WFlMS)

Between tracks: 60 dB
Between channels: 30 dB
3%

60 dB

DC Micro motor
Permalloy

CD/Line in: 500mV, 220k ohms
8 ohms to 300 ohms

4 ohms to 8 ohms